Three-dimensional “coordinate measuring machines” (CMM) are well-known in the field of metrology. A CMM allows a user to precisely measure an object in three-dimensional space by precisely recording a number of points on the object. One type of CMM is known as a “portable CMM” since it can be readily transported/set-up where needed. A portable CMM includes a probe that is hand-held and manipulated by a user. In a measurement operation, the user touches the probe to a number of points on an object being measured. The three-dimensional coordinates of the points are recorded on a computer coupled to the probe in a hardwired or wireless fashion.
Between one or more probe touches, the user must use the computer to identify how the probe is about to be used, i.e., identify the operational mode of the probe. For example, if the user is about to measure points on a circular portion of an object, the user must “tell” the CMM's computer that the next series of probe touches should be fit to a circle. Currently, the user supplies the CMM's computer with an operational mode selection via a mouse of keyboard coupled to the CMM's computer. That is, the user generally releases the probe, sets it down, etc., and then uses his hands to make his mode selection using the CMM's mouse/keyboard. The user must then pick up the probe and perform his one or more measurement “touches” associated with the mode selection. To change modes (or calibrate the CMM, edit settings such as instrument sampling rate, etc.), the user must repeat the “probe release, computer input, probe pick-up” sequence. Over the course of a typical measurement operation, this back-and-forth handling can be time-consuming and tedious.